A LANDFILL site closure has put 35 jobs at risk after the Environment Agency moved to stop poisonous mercury leaking into groundwater.

The Gazette understands that Silent Valley Waste Services Ltd, which operates the landfill site near Cwm and Waunlwyd, will receive no more waste after March 31.

The Environment Agency has issued a closure notice to the company, saying seepage of mercury and other harmful materials from the waste into groundwater is a “long-term risk of pollution”. Groundwater is being pumped to the sewer for treatment as a precautionary measure to minimise spread of pollution.

And as of Tuesday, March 1, the company could not promise their employees’ positions would be safe.

A director at Silent Valley, Clive James, told the Gazette: “We are in the position of consulting with the workforce on the potential for redundancies. This dialogue has to take place.”

Both Blaenau Gwent and Caerphilly County Borough Councils use the services of Silent Valley for waste disposal. The landfill is situated on the site of a former slag-disposal plant used for tipping waste from the Ebbw Vale steelworks.

While the Environment Agency say the leak poses no immediate health risks to either the public or site employees, contaminated groundwater is having to be pumped to sewers for treatment to prevent any spread of harmful metals.

A spokesman for the Environment Agency said: “We have served a notice to start the closure process at Silent Valley landfill due to the long-term risk of pollution caused by contamination leaking from the waste.

“The contamination includes very small traces of metals such as mercury and nickel and other pollutants such as ammonia.

“The site is still operating as normal but we are working towards closing the site.

“There is no immediate hazard to the public, the workforce or the environment as a result of this pollution.”

Cwm councillor Peter Abbott said: “Any mercury I don’t like the sound of, but my understanding was that it is coming from old mine workings.

“The area is littered with iron ore mines.

“But wherever it’s coming from, if there’s any danger at all I would shut it down. I don’t want to see one person harmed from any potential danger.

“This is the shot in the arm that we cannot continue landfilling.”

A spokesperson for Caerphilly Council said: “We have received notice that from March 31, 2011, Silent Valley Waste Services will no longer be able to receive waste, and would have to terminate their contractual arrangements with the authority.

“We have a contractual agreement with another Waste disposal contractor and will utilise this facility from April 1, 2011.”